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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 27 |
| 5 | 86 |
| 6 | 199 |
| 7 | 1678 |
| 8 | 16979 |
| 9 | 137510 |
| 10 | 291999 |
| 11 | 1013507 |
| 12 | 5359534 |
| 13 | 11732575 |
| 14 | 17092109 |
| 15 | 28824684 |
| 16 | 1458326309 |
| 17 | 1487150993 |
| 18 | 2945477302 |
| 19 | 7378105597 |
| 20 | 39836005287 |
| 21 | 126886121458 |
| 22 | 293608248203 |
| 23 | 2475752107082 |
| 24 | 25051129319023 |
| 25 | 202884786659266 |
[1,1,2,5,27,86,199,1678,16979,137510,291999, 1013507,5359534,11732575,17092109,28824684, 1458326309,1487150993,2945477302,7378105597, 39836005287,126886121458,293608248203, 2475752107082,25051129319023,202884786659266] |